Based on the popular Chorus RF Laptimer, this ESP32 port provides many significant advantages, not only does the ESP32 provide much more processing power than AVR based Arduino boards but it's built in Wifi and Bluetooth networking greatly improve connectivity options.
Compared to the original ChorusRF Lamptimer this ESP32 version only requires one RX module per pilot and a single ESP32 (nodemcu or similar) board. This allows you to connect your Lap timer wirelessly with no extra hardware required.
Hardware construction is also simplified as both parts are 3.3v logic and there is no need for level shifting or resistors.
Added OLED and VBAT measurement support Auto RSSI threshold setup is also not implemented, just set thresholds manually for now.
Added inital webserver configuration portal https://www.youtube.com/watch?v=BVd2t0yO_5A/0.jpg
This devices communicates using the Chorus RF Laptimer API and should work with LiveTime (untested) as well as the Chorus RF Lap timer app https://play.google.com/store/apps/details?id=app.andrey_voroshkov.chorus_laptimer
Construction is easy and only requires some basic point to point wiring of each module to the ESP32 board.
See HardwareConfig.h for pin assignments, it is possible to change any pin assignments apart from ADC channels and I2C pins 21 & 22. Note that pin assignments are GPIO hardware pin numbers and not pin numbers specific to the particular ESP32 development board you may be using. IMPORTANT NOTICE: PCB DESIGNS ARE BEING TESTING AND HARDWARE PINOUT WILL CHANGE IN THE NEAR FUTURE!
The images below show a construction using an ESP32 OLED board, it is recommended to use the more standard NodeMCU at the moment.
The Chorus32 Lap timer was compared to the $600USD ImmersionRC LapRF 8-Way at a local indoor event, arguably the worst conditions due to multipath and reflections. Results are presented below, you can see that the Chorus32 very closely matches the measured lap times of the LapRF.
Due to the fact that both the Bluetooth and Wifi stack are used quite alot of program memory is required. To compile the project you must choose 'Partition Scheme' -> Minimal SPIFFS in the Arduino IDE. Board should be selected as 'ESP32 Dev Module' in most cases.
As we are not supoorting bluetooth for now and are using the SPIFFS partition leave the Partition Scheme as 'default'